Monoclonal antibodies to antigens associated with transitional cell carcinoma of the human urinary bladder

Abstract
Spleen cells from BALB/c mice immunized with cells derived from transitional cell carcinomas (TCC) of the human urinary bladder were fused with mouse myeloma Sp 2/0 Ag14 cells. Monoclonal antibodies from 6 established hybridomas were investigated for specificity in a cell ELISA and in indirect immunofluorescence against a large panel of fixed intact cells. Three of the antibodies reacted with half or more of the 8 bladder tumors and with a few unrelated tumors. The did not react at all with malignant or normal cells of hematopoietic origin. A 4th antibody reacted with 7 of 8 bladder tumors. It also reacted weakly with a prostatic carcinoma, with 5 of 6 malignant or transformed B cell lines, and with a subpopulation of normal lymphocytes, but not with any of the other cells on the test panel. These 4 antibodies did not react with cells derived from normal urothelium. These antibodies might recognize cell-type-restricted antigens associated with malignancy. Another antibody reacted with almost all urothelium-derived cells. It also reacted with 3 of 3 melanomas but not with any other cells on the panel. The 6th antibody reacted with 32 of the 37 cells tested. The spectrum of reactivities displayed by the antibody suggested that it recognizes HLA antigens.